Johnny Carson, Iron Throne from 'Game of Thrones'

Carson Entertainment; HBO

The prize in the late-night battle, equivalent to the Iron Throne of "Game of Thrones," is the top spot in the Nielsen ratings, which has traditionally been held by whomever sits at the Burbank desk once held by the "king of late night," Johnny Carson, on NBC's venerable "Tonight Show."

The prize in the late-night battle, equivalent to the Iron Throne of "Game of Thrones," is the top spot in the Nielsen ratings, which has traditionally been held by whomever sits at the Burbank desk once held by the "king of late night," Johnny Carson, on NBC's venerable "Tonight Show." (Carson Entertainment; HBO)

The prize in the late-night battle, equivalent to the Iron Throne of "Game of Thrones," is the top spot in the Nielsen ratings, which has traditionally been held by whomever sits at the Burbank desk once held by the "king of late night," Johnny Carson, on NBC's venerable "Tonight Show."